Push-button switch construction



1944- K. KNUDSEN 2,355,303

PUSH BUTTON SWITCH CONSTRUCTION Filed March 28, 1941 2 Sheets-Sheet l INVENTOR 6W0 111M055 ATT RNEY W BY Aug. 8, 1944. 'K KNUDSEN 2,355,303

PUSH BUTTON SWITCH CONSTRUCTION Filed March 28, 1941 2 Sheets-Sheet 2 INVENTOR M00 261/0055 Patented Aug. 8, 1944 PUSH-BUTTON SWITCH CONSTRUCTION Knud Knudsen, Danbury, Conn., assignor to Edwin G. Gaynor, Fairfield, Conn.

Application March 28, 1941, Serial No. 385,593

17 Claims.

This invention relates to push button switch construction and more particularly to the construction of two-button switches adapted for use in fluorescent lighting systems in which one push button switch is actuated to initiate light emission by the lamp and the other is actuated to halt the operation of the lamp.

One of the objects of this invention is to provide a push button switch construction that will be simple and inexpensive to manufacture, compact, strong and durable, and of dependable action in practical use. Another object is to provide a push button switch construction in which individual parts are of simple and inexpensive manufacture and capable of rapid or quantity manufacture, and so constructed that their assembly into a complete switch unit may be effected with facility, efficiency and dependability. Another object is to provide a switch construction of the just mentioned character in which assembly may be achieved with minimum or simple tool operations. Another object is to provide a push button switch construction in which the parts are so constructed as to permit the achievement, in substantial measure, in course of manufacture, of the many advantages of simplicity and low cost by way of stamping or punching operations.

Another object is to provide a push button switch and condenser assembly or unit, particularly adapted for use in so called fluorescent lighting systems, that will be of simple and compact and inexpensive construction, and of dependable action in use. Another object is to provide a construction of the just mentioned character in which the various parts are constructed to facilitate step by step assembly or building up of the ultimate unit of switch and adjunct like a condenser, and in which electrical interconnection and maintenance of final assembly may be achieved in a simple and reliable manner.

Another object is to provide a push button switch construction in which assembly and mounting of various contacts are facilitated. Another object is to provide a push button switch construction in which the terminal or circuitconnector element and contact may be insulatingly mounted in a simple and inexpensive manner and bring into exposure at the desired points the terminal or connector element and the contact element. Another object is to provide a simple and dependable assembly and mounting of connector and contact elements with an electrical device such as a condenser to form therewith a compact and dependable unit for ready connection into the intended circuit. Another object is to provide a built-up push button and contactor construction whose parts are of inexpensive construction or manufacture and are capable of rapid and inexpensive but reliable assembly. Another object is to provide, in a push button switch construction, for the de pendable insulation of the contactor actuated by the button. Another object is in general to provide an improved push button switch and assembly. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts as will be exemplified in the structure to be hereinafter described and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings in which is shown an illustrative embodiment of my invention,

Figure l is a plan view of the assembled switch construction;

Figure 2 is a front elevation with certain parts broken away and other parts shown in central vertical section;

Figure 3 is an end elevation as seen from the left in Figures 1 and 2;

Figure 3 is a front elevation like that of Figure 2, certain parts being broken away and certain other parts being shown in section, showing a modified form of switch construction;

Figure 3 is a front elevation like that of Figure 2, certain parts being broken away and certain other parts being shown in section, showing another possible form of making certain electrical connections; and

Figure 4 is a perspective view of the preferred forms of the various parts that go to make up the construction, the parts being shown detached from each other and substantially in the sequence in which they are preferably related to one another in the course of their assembly.

Similar reference characters refer to similar parts throughout the several views in the drawings.

For purposes of illustration, let it be assumed that the push button switch construction is to be employed in connection with a so-called fluorescent lighting system in which the lamp, usually employing mercury vapor, is provided with a heater or filament element which, to start the lamp, is energized, usually momentarily, and in 55 which, to stop the operation of the lamp, the main lamp circuit is interrupted, usually only momentarily; in such systems or such an arrangement it is desirable to relate to the lamp circuits an impedance usually and preferably in the form of a condenser, in order to counteract or eliminate such reactions of the operation of the lamp upon the power or supply circuit as would, for example, cause interference with radio or like reception by instruments powered from the same supply circuit or by instruments located within the influence of the lamp or its associated circuit or circuits. Where the switch is intended for such an installation it is provided with a normally open switch connected to the heater or filament circuit so that the latter may be energized for a suitable period of time to start the lamp, and with a normally closed switch in the main lamp circuit and the actuation of which open-circuits the lamp for a sumcient interval of time to halt the light-emitting discharge in the lamp; where an electrical device such as a condenser is needed, as in the above-stated i1- lustration, I preferably incorporate the device mechanically and electrically into the switch assembly to form therewith a single compact unit.

In the preferred form of carrying out my invention, I preferably provide a base generally indicated by the reference character I and preierably make it up of two sheet members H-if of a suitable insulating material, such as fiber, hard rubber, or the like, of suitable thickness, illustratively rectangular in shape and adapted to be superimposed one upon the other; they are preferably of identical or matching outline, It

as is better shown in Figure 4, and along their longitudinal edges are provided with registering spaced notches or cut-outs l3. They may thus be stamped out by the same dies.

Sheet member i2 is pierced or apertured to coact with the sheet member II to insulatingly mount and support the desired connector-contact elements of which two pairs are employed where the switch is made up to control two circuits. Thus, referring to Figure 4, where the parts are shown in inverted positions as compared to Figures 1, 2 and 3, sheet member I2 is provided at its left-hand end with two pairs of apertures l4|5 shaped substantially as shown and at its right-hand end is provided with two pairs of similar apertures Iii-41. In such case, also, two pairs of connector-contact elements are employed and the pair for the apertures I 4-15 is shown in Figure 4 at l8 and the pair for the holes l6l'! is shown at l9. They are preferably made from initial stampings of the same dimensions, preferably of a material having good spring characteristics, like a suitable brass or phosphor bronze, and in so far as their interrelationship with their respective apertures in the sheet member [2 and their coaction with the sheet member II are concerned, they are preferably identically shaped, being given, in the illustrative embodiment, a succession of bends, preferably right angle bends, each thus being given a somewhat repeatedly reentrant form or shape, as shown, the width of the apertures l4, l5, l6 and l! in the direction transversely of the longitudinal axis of the sheet member l2 being slightly in excess of the width of the material of the metal members l8, l9.

In so shaping the elements l8, l9, and this may be done by suitable dies, each element is thus provided with a part 20, hereinafter called the connector part, preferably apertured as at 2|,

Ill)

displaced from the plane of two fiat parts 22, 23 by a distance on the order of the thickness of the sheet member l2 so that, viewing Figure 4, the parts 22 and 23 may rest flatwise against the upper face of the sheet member l2 while the connector parts 20 of elements I8 are projected downwardly through the holes l4 to become exposed at or below the plane of the under face of the sheet member 12, while connector parts 20 of the elements I9 become similarly exposed through the holes l6 at the other end of the sheet member l2.

The contact parts 24 of elements IS, in effecting the above relationship to the sheet member l2, are snaked downwardly through the holes Hi, the contact elements 24 being downwardly displaced from the plane of the parts 22, 23 so that when this assembly to the sheet member I2 is completed, the two contact elements 24 extend substantially parallel to each other, each on one side of the longitudinal axis of the sheet member I2, and each closely adjacent to the under face of member l2 but somewhat spaced therefrom to allow for a suitable range of resilient or springy action toward or away from the sheet member l2, as appears better in Figure 2.

In a generally similar way, the contact parts 25, 25 of the elements l9 are snaked through the holes l1, [1, respectively, whence the parts 22, 23 are brought flatwise against the upper face of the sheet member l2, as seen in Figure 4, and the connector parts 20 are projected into or through the holes l6, respectively. But in the illustrative form, contact elements 25, 25 become fixed in substantially parallel relationship, each to one side of the longitudinal axis of the sheet member I 2, but both spaced substantially from the under face of sheet member l2 and parallel thereto, as is better shown in Figure 2. Because of this greater spacing, contact parts 25 per se are a little shorter than the contact parts 24, where the elements I8 and I9 are made up from the same initial stampings.

With the elements l8, l9 thus interlocked with the sheet member [2 (still referring to Figure 4), and hence with the connector elements 20 of all of them and with the contact elements 24 and 25 exposed at or below the under face of the sheet member l2, leaving only the parts 22 and 23 overlying the upper face of the sheet member 12, the next step or steps of assembly may be proceeded with and here I prefer to employ two preferably identical push button contactors indicated at 21 and 28, and a sheet metal housing generally indicated at 29.

In Figure 2 the push button contactors 21 and 28 are shown in cross-section, and, as above indicated, they are preferably of identical construction, being preferably made up of inexpensively manufactured individual elements capable of rapid and reliable assembly. Thus, I preferably employ, in making up the button-contactors, a hollow cylindrical element or button 31, preferably made of a suitable insulating material, such as a molded plastic or suitable non-metallic rod material cut off into suitable lengths and bored or drilled out at one end to a suitable depth. Resting against the open end is a contactor 32, in the form of a simple metal washer, whose round hole is of substantially the same diameter as the hole in the button 3|, and it is held to the latter preferably by means of a hollow or sleeve-like member 33, conveniently in the form of an eyelet having an outwardly extending peripheral flange 34 between which and the end of ,Mmmmmlllllnl the button 3| the washer-shaped contactor 32 is clamped or held as the tubular or hollow fastening member 33 is forced into the hollow button 3| by a suitable friction or press fit. The outside diameter of the contactor 32 is sufficient to have the latter bridge over or engage the laterally spaced contact parts 24-24 or 25-2 5, as the case may be, in the assembled switch structure.

The housing 29 is preferably constructed so that it may be produced by simple punch-press operations and it is conveniently open-ended, having a plane top wall 36 and two spaced parallel side walls 31, 38 carrying sets of spaced lugs or ears 39, the spacings of which are commensurate with the spacings of the cut-outs or notches I3 of the sheet members H and I2 (see Figure 4). Along the central longitudinal axis of the top wall 36, the latter is provided with apertures 4|, 42 formed preferably by tube-like extensions 43 and 44 drawn out of the sheet metal of the wall 36, and dimensioned for easy sliding reception of the buttons 3 I.

Recurring now to the assembly, the housing 29 is positioned upside down, as in Figure 4, whence two annular members or washers 46 of insulating material having holes diametered the same as the diameters of the holes 4|, 42 are rested upon the face of the wall 36 and through the left-hand washer 45 and into the aperture 4| is now positioned the push button contactor 21, the material of the button SI and the washer 46 dependably insulating the metal parts of the button-contactor 21 from the metal of the housing 29.

The other button-contactor 28 is now suspended with its contactor 32 bridged across the two laterally spaced contact parts 25 of the elements I9, the latter with the elements I8 having been assembled to the sheet member I2, as abovenoted, whence this assemblage, with the buttoncontactor 28 thus suspended, is brought down, as viewed in Figure 4, toward the wall 36 of the housing 29, button 3! entering the hole 42, and as the relative movement is continued the ears 39 enter the cut-outs !3 in the sheet member I2 whose two longitudinal side portions are brought to rest against the upwardly exposed edges of the side walls 31 and 38.

Sheet member I2 has in it two holes 48 and 49 of a diameter about the same as the inside diameter of the tubular secu ing devices 33 of the button-contactors, holes 48 and 49 being coaxial respectively with the button holes 4| and 42 in the housing 29. Through the holes 48 and 49 are now entered helical springs and 52, respectively, the latter being long enough in their normal extended position to enter into the tubular securing members 33 of the button-contactors and to bottom against the inwardly directed flanges 59 of the latter. With the completion of the assembly of springs 5|, 52 as just described, they project upwardly, as viewed in Figure 4, beyond the upper face of the sheet member I2, and now sheet member I I is brought down upon and face to face with the sheet member I2, compressing the springs 5|, 52 and ears 39 of the housing 29 entering the notches I3 of the sheet member I I. Sheet member II thus rests against the parts 22, 23 of the connectorcontact elements Iii, I9 and with sheet members I I and !2 thus held together and with both held assembled to the housing 29, as by bending over the securing ears 39, the assembly of the switch structure per se is completed.

However, and as above pointed out, where the switch structure is to have associated with it an electrical device, such as a condenser, before bending over the ears 39 of the housing 29, I next relate to the exposed face of the sheet member II a condenser 54 dimensioned to fall within the confines of the sheet member II and in the illustration being in length about half the length of the sheet member II. It may be of any suitable construction and is provided with two terminal or connecting wires 55 and 56 brought out from one end.

In such case, I provide sheet member II with two holes 51, 58 (see Figure 4) substantially alined respectively with the holes I4, I4 in the sheet member I2, and in bringing the device or condenser 54 to rest against the exposed face of the sheet member II, the two terminal wires 55, 55 thereof are threaded or snaked, respectively through the holes 51 and 58 and through the apertures 2| in the connector parts 29 of the two connector-contact elements I8.

Next there is placed over the device 54 a protective insulating sheet 60 of a suitable material like suitably treated paper or like fiber, the element 6|) enveloping the device 54 and having its edge portions 69 and BI) resting against the longitudinal marginal portions of the sheet member I|!. Superimposed upon the device 54, covered by the sheet 63, is a U-shaped sheet metal part 6| whose top wall 6| and side wall tI are dimensioned snugly to receive therein the sheetcovered device 54 and, with the sheet member I I to form a snug casing or enclosure for the device 54.

The member 6| has side flanges 62 and. 63 to rest over the edge portions 99* and 69 of the sheet member 60 and these flanges are notched or cutout as at 64 to receive therein a corresponding number of the upstanding ears 39 of the housing 29, and where the condenser structure and its support or cover oi are only about half as long as the sheet member II and where the housing 29 has six ears 39, the part 6| has its notches $4 spaced to receive the left-hand end pair of ears 39 and the middle pair of ears 39, as viewed in Figure 4.

All of the ears 39 may now be bent over, by any suitable means and under sufficient force to clamp the parts I2, II, 60 and 6| snugly or tightly together and against the edges of the side walls 31, 38 of the housing 29, whence the assembly is completed and the device is ready for use or installation, appearing in assembled form. as shown in Figures 1, 2. and 3 and substantially ready for installation and use. In

this latter connection, it might be noted that the condenser terminal wires 55 and 56, brought through the apertures 2| in the connector parts 2|! of the elements I3. may be cut off, leaving a sufiicient length, as is better shown in Figure 1, to be bent against and overlie the connector parts 29 and hold them against being withdrawn unintentionally.

The connector parts 20 of the two pairs of switch elements I8 and I9 will be seen to be conveniently exposed upwardly and thus ready and conveniently available formaking electrical connection thereto of the circuit conductors, as by soldering the latter thereto, the soldering operation serving also to permanently fix the electrical connection of the condenser lead wires 55 and to their respective connector parts 20, 20 in the event that, as may be desired, they are not otherwise anchored or secured.

As better appears from Figure 2, the springs SI, 52, with their lower ends held in alinement by the holes 48 and 49, respectively, hold the button-contactor structures 21 and 28, respectively, in their normal uppermost position, movement in upward direction being limited by the contactor members 32 of the button-contactor structures and their coacting parts. Thus, spring 5| holds the structure 21 in uppermost position as determined by the contactor washer 32 pressing the insulating washer 46 against the top wall 35, but it will be noted that the upward push of the spring is transmitted to the washer contactor 32 by the tubular securing device 33, thus achieving the advantage of relieving the button 3| from strain, particularly strain in a direction to undo the friction fit between the button 3I and the securing device 33.

Similar relationships of actions and relief of strain occur with respect to the button-contactor 28 excepting that the contact parts 25, overlying the contactor-washer 32, in the first instance take the upward pressure of the contactor 32, thus to maintain a good circuit-closing relationship, while the insulating washer 45, overlying the spaced contact parts 25, prevents the latter from being brought into contact with the housing wall 36.

Depression of button-contactor 21 carries the contactor 32 downwardly and into bridging contact with the two spaced contact parts 24, the range of resilient yieldability of the latter in a direction downwardly, as viewed in Figures 2 and 3, achieving a certainty or nicety of bridging ac tion, it being noted that the downward push of the button 3| is transmitted directly to the contactor 32 and again the friction fit between the parts 3| and 33 does not become strained.

Depression of button-contactor 28 brings its contactor 32 out of bridging relationship to the contact parts 25 of the elements I9, thus inter- I rupting the circuit in which they are included. Also, release of either button-contactor effects quick restoration of the respective button-contactor under the action of its spring, to effect restoration to normal position or positions, as shown in Figure 2.

Also, I dependably guard against breakage or chipping of the insulating material of the buttoncontactor constructions for, should either button-contactor be quickly released as frequently occurs in practice so that its spring snaps it upwardly at substantial velocity, the resultant strains or stresses accompanying the halting of the upward movement are taken up by the metal parts of the button-contactor structures, such as parts 33 and 32, the non-metallic material of the button 3| being relieved of such strains and stresses and chipping or breakage thereof guarded against.

As above pointed out, in the construction of Fi ures 1, 2 and 3, the connector parts 20 of the switch elements I8 and I9 are conveniently accessible for making electrical connection thereto of the circuit conductors, as by soldering, but where it is desired to anchor or clamp the circuit conductors mechanically, I prefer to employ a clamping arrangement like that shown in Figure 3 where, in course of assembly, as above described in connection with Figure 4, I accommodate in each space overlying the connector parts 20 of the elements I8 and I9 of Figure 4 a square nut 65 (Figure 3 and pass through each aperture or hole 2| a screw 66 and thread it into the nut 65, the latter being neatly accommodated in the bend of the switch elements and being by the two side walls of the bend held against rotation. Thence I proceed with the assembly as described above in connection with Figure 4, but in such case I prefer to provide the sheet member II with four holes 51, preferably round and of larger diameter than the threaded shank of the screw 66 and respectively alined center to center with the four holes I4, I4 and I6, I6 in the sheet member I2.

When the two sheet members are placed together, as above described, the relationship of the just described parts is as shown in Figure 3', each nut 65 becoming closed in or encased and thus it cannot become lost, even if the screw 66 is detached therefrom. Also, it may be noted that, in carrying on the step by step assembly the four nuts 65 may be simply set into the U- shaped bends bottomed by the connector parts 2!! (Figure 4), the latter extending downwardly through the holes I4, l4 and I6, I6, respectively, subsequently closed over by the sheet member I I, and thereafter, at any suitable stage, even after completing the clamping over of the ears 39, the screws 66 may be added, simply inserting them through the holes 2| and threading them into the encased nut 65 which, though preferably accommodated with a suitable degree of play or looseness, nevertheless interfit with the four side walls of the space so that they are held against rotation. In any case, a secure clamping of the circuit conductors under the head of the screw 66 and against the connector part may be effected, the substantial thickness of the nut and the number of threads thereby accommodated in it enhancing the security and strength of such clamping action. Any surplus lengths of the screws 56 are accommodated in the holes 6 provided in the sheet member II.

Where the construction includes an electrical device like the condenser 54 above described, the two lead wires 55 and 56 of the latter are snaked through the two holes 6T, 6T, respectively juxtaposed to the holes I4, I4 of the sheet member I2 and in any suitable manner looped around a screw shank projecting through the hole 2| and then a nut applied so that the loop or turn of the lead wire lies between the nut and the flat connector part 29. The play or space between the nut and the two opposed side walls of the hole I4 in the sheet member I2 provide ample space for leading the lead wire or wires past either of two opposed sides of the nut, the remaining two opposed sides of the nut, as shown in Figure 3 being preferably in relatively snug contact with the vertical portions of the switch elements so that these metal parts of the latter resist rotation of he nut.

Subsequent clamping of the circuit conductor between the head of the screw 66 and the upper face of connector part 20 also effects clamping of the lead wire between the under face of the connector part 20 and the nut 65, it being noted that this latter clamping action is not accompanied by relative rotary movement between the clamping parts and hence injury to the lead wire is guarded against.

Or, lead wires 55 and 58 (Figure 4), after being passed through the holes 51 and S3 in the sheet member II or through the above-mentioned holes 51, 61 where the binding screw arrangement is employed, as in Figure 3 may be bent over against the under face of the sheet member II, as seen in Figure 4, keeping them preferably parallel and out of contact with each other, so that when the two sheet members II and 12 are, with their associated elements, brought together as above-described, these lead wires contact and rest against respective portions of the contact or switch elements l8, I8, such as the portions 23 thereof, as is better shown in Figure 3*. As there shown, each lead wire, such as lead wire 55, together with the portion 23 of the switch element 18, is thus interposed between the adjacent faces of the sheet members II and I2 and when the assembly is completed and the clamping ears 39 bent over under suificient force to press sheet member l2 and its associated contact elements against the sheet member II, the lead wire and portion 23, in each case, are clamped together between the opposed portions of the sheet members II and 12. The lead wires thus become mechanically anchored and also electrically connected to their respective switch elements and with the arrangement of Figure 3 greater simplicity and speed of assembly may be. achieved.

The construction will thus be seen to be dependable and, moreover, though assembly, as in the above-described illustrative sequence of steps, may be speedily effected with little use of tools, disassembly during normal use of the construction is dependably prevented. The connector-contact elements are dependably anchored in their intended positions, dislodgment cannot take place, and long-continued dependability is assured. The device, such as the condenser 54, is not only dependably clamped between the composite base member and the part 6| and thus held against dislodgment, but also is sufiiciently encased and on its exposed sides covered by the sheet metal element BI and thus dependably protected mechanically against injury in handling, installation, use, or the like.

' Thus, it will be seen that there has been provided in this invention a construction in which the various objects heretofore noted, together with many practical advantages, are successfully achieved, and it will be seen that the device is of a thoroughly practical character and well adapted to withstand the varying conditions of hard practical use.

As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. A push button switch comprising two sheet members of insulating material adapted to rest one against the other, at least one of said sheet members having aperture means therein, a plurality of sheet metal connector-contact elements each having, a contact portion overlying one face of said one sheet with another portion resting against the other face of said one sheet and an intermediate portion extending through said aperture means, the other of said sheet members engaging against said other face of said one member with said second-mentioned portions of said plurality of elements positioned between said two sheet members, said aperture means locating said connector-contact elements in spaced relation, means including a push button for coacting with said connector-contact elements, and means for supporting said push button and said two sheet members with said push button and connector-contact elements in cooperating relation and for holding said two sheet members against separation and thereby holding said second-mentioned portion of each of said connector-contact elements substantially clamped between said two sheet members.

2. A push button switch as claimed in claim 1 in which each of said connector-contact elements has a connector portion for electrically connecting thereto a conductor, at least one of said sheet members being cut away at points corresponding to the location of said connector portions to expose the latter therethrough' 3. A push button switch as claimed in claim 1 in which said supporting means comprises a sheet metal housing structure having a top wall with an aperture therein for receiving said push button and spaced side Walls provided with means for engaging said two sheet members and holding them against separation.

4. A push button switch construction comprising a metal housing substantially U-shaped in cross-section and having an aperture in the intermediate portion thereof, a push button slidable in said aperture, two sheet members of insulating material resting fiatwise one against the other and at least one of them being apertured, a sheet metal contact element for coaction with said push button and having portions bent reentrantly and interfitted with said apertured sheet member with at least one portion extending between said two sheet members, and means securing said two sheet members to the two side portions of said housing and for holding said sheet members against separation and thereby holding said contact element against disengagement from said apertured sheet member.

5. A push button switch comprising a housinglike structure having in the top thereof an aperture with a push button contactor structure slidable in said aperture and having contact means positioned in the path of movement of the contactor of said push button contactor structure, the latter comprising a push button of insulating material having a substantially cylindrical bore therein extending from and open at the inner end thereof, a metal contactor having a central apertured portion resting against said inner end of said button and a cylindrical member peripherally flanged at its lower end extending through the apertured portion of the contactor and having a diameter related to the diameter of said bore for force-fitting thereof into said bore and said cylindrical member being force fitted into said bore of said button for holding itself and said button assembled and to hold said contactor between the end of'the latter and the peripheral flange.

6. A push button switch as claimed in claim 5 in which said cylindrical member is hollow and open at its exposed end, said housing-like structure and said push button having means for limiting movement of the button in a direction outwardly of said structure, and a coil spring for opposing movement of said button-contactor structure inwardly, said coil spring entering said hollow cylindrical member, the latter having means adjacent its inner end for engaging the end of said spring and said spring thereby acting directly upon said hollow cylindrical member and in a direction relative to said button to tend to force said hollow cylindrical member intothe said bore in the same direction in which it was force-fitted into the bore.

7. In push button switch construction, a push button of insulating material having a substantially cylindrical bore therein extending from and open at one end thereof, a metal contactor having a portion resting against the open end of said button, and means holding said contactor assembled to said button comprising a tubular metal member having external cross-sectional dimensions proportioned to the cross-sectional dimensions of said bore for relatively tight interfitting therewith, said tubular metal member being entered into and thereby frictionally held in said hollow button and having at its exposed end a lateral flange for holding said contactor against said end of said button.

8. In push button switch construction, a push button of insulating material having a substantially cylindrical bor therein extending from and open at one end thereof, a metal contactor having a portion resting against the open end of said button, means holding said contactor assembled to said button comprising a tubular metal member having external cross-sectional dimensions proportioned to the cross-sectional dimensions of said bore for relatively tight interfitting therewith, said tubular metal member being entered into and thereby irictionally held in said hollow button and having at its exposed end a lateral flange for holding said contactor against said end of said button, and a coil spring having an end entered into said tubular metal member, the latter having means for engaging the end of the spring, said spring thereby acting directly upon said tubular metal member and in a direction to oppose movement of said tubular member outwardly from said bore.

9. A switch construction comprising a sheet metal housing having an apertured top wall and spaced side walls, said side walls having at their ends clamping means, push button means coact ing with said apertured top wall, contact means comprising at least one sheet metal contact element, two sheet members of insulating material bridged across said side walls adjacent their ends, the innermost thereof being cut away and having said contact element interfitted with its cut away portions, an electrical device adjacent the outer face of the outermost of said sheet members and having supporting means therefor, said clamping means clamping said two sheet members and said supporting means together and to said two side walls. 7

10. A switch construction comprising a sheet metal housing having an apertured top wall and spaced side walls, said side walls having at their ends clamping means, push button means coacting with said apertured top wall, a sheet member of insulating material bridged across said side walls and having cut away portions and sheet metal contact means bent and shaped and interlocked with said sheet member at said cutaway portions, thereby exposing a portion interiorly for coaction with said push button means and exposing at least one portion externally of said sheet member, a sheet member of insulating material resting against said first-mentioned sheet member and the portion of said contact element externally exposed, and an electrical device having means for supporting it adjacent said second sheet member, said clamping means holding said supporting means and both of said sheet members against separation and to said housing.

11. A switch construction comprising a sheet metal housing having an apertured top wall and spaced side walls, said side walls having at their ends clamping means, push button means coacting with said apertured top wall, a sheet member of insulatin material bridged across said side walls and having cut away portions and sheet metal contact means bent and shaped and interlocked with said sheet member at said cut away portions, thereby exposing a portion interiorly for coaction with said push button means and exposing at least one portion externally of said sheet member, a sheet member of insulating material resting against said first-mentioned sheet member and being cut away at a portion thereof to make accessible therethrough said lastmentioned portion of said contact means, an electrical device having conductive terminal means and having means for supporting it adjacent said second sheet member with its terminal means extending through said cut away portion and into electrical connection with said exposed portion of said contact means, said clamping means holding said two sheet members and said supporting means together and to said housing.

12. A push buttton switch construction comprising a metal housing substantially U-shaped in cross-section and having an aperture in the intermediate portion thereof, a push button slidable in said aperture, two sheet members of insulating material resting flatwise one against the other and at least one of them being apertured, a sheet metal contact element for coaction with said push button, said sheet metal element being bent reentrantly and having an apertured portion exposed at one end of the aperture in aid apertured sheet member and having at least one other portion extending between said two sheet members, a nut accommodated underneath said first-mentioned portion of said sheet metal element, means securing said two sheet members to the side portions of said housing and for holding said sheet members against separation and thereby holding said contact element against disengagement from said apertured sheet member and holding said nut in place, and a screw extending through the aperture in said apertured portion of said sheet metal element and in threaded engagement with said nut.

13. A push button switch construction as claimed in claim 12 in which said reentrantly bent sheet metal contact element has opposed portions respectively engaging opposed sides of the nut and thereby hold it against rotation.

14. A switch construction as claimed in claim 11 in which said externally exposed portion of said contact means has an aperture and said conductive means of said electrical device passes through said aperture, and means mechanically anchoring said terminal means to said portion.

15. A switch construction as claimed in claim 11 in which said externally exposed portion of said contact means has an aperture therein, a nut underlying said apertured portion, a screw passing through said aperture and threaded into said nut for making an external electrical connection, said terminal means of said electrical device being electrically and mechanically connected to said contact means by clamping pres-- sure exerted by said screw and nut.

16. A switch construction as claimed in claim 11 in which said terminal means of said device and the portion of said contact means with which it is in electrical connection rest one against the other and in between said two sheet members, said clamping means in holdingsaid two sheet members together causing the latter to hold said terminal means and said portion pressed together.

17. A push button switch construction comprising a housing-like structure having in the top thereof an aperture with a push button contactor structure slideable in saidv aperture and having the bottom thereof formed of two sheet members of insulating material resting flatwise one against the other and at least one of them being apertured, a sheet metal contact element having portions bent re-entrantly and interfitted with said apertured sheet member with at least one portion extending between said two sheet members, the innermost of the latter having an aperture substantially aligned with the aperture in the top, said contactor structure comprising a hollow push button of insulating material open at the inner end thereof and having a centrally apertured metal contactor resting against its inner end and a hollow cylindrical member extending through said apertured metal contactor and frictionally held in said hollow push button, said cylindrical member being peripherally flanged at its lower end to hold said metal contactor in position, and a coil spring having one end engaging said hollow cylindrical member interiorly thereof and having its other end extending through the aperture in said inner sheet member and resting against the inner face of said outer sheet member.

' KNUD KNUDSEN. 

